ADU Regulations in Gresham, Oregon
Multnomah County's second-largest city, Gresham permits ADUs by right under Oregon's HB 2001. The city actively encourages ADU construction through reduced System Development Charges (SDCs), making it an affordable option for property owners.
Below is a summary of the key zoning rules applicable to Accessory Dwelling Units in Gresham as of 2026. Regulations are governed by Oregon's HB 2001 (2019) which requires ADU approval by-right in all residential zones statewide.
| Regulation | Requirement |
|---|---|
| Maximum Size | 1,200 sq ft |
| Property Setbacks | 5 ft rear, 5 ft side |
| Extra Parking Required | Not required |
| Owner Occupancy | Not required |
Additional Local Requirements for Gresham
- ADU by right in all residential zones
- Minimum 200 sq ft
- Max height: 20 ft
- System development charges may be reduced for ADUs
📥 Download the Complete Gresham ADU Cheat Sheet
Get the step-by-step permit checklist, official government forms, direct planning department contacts, and estimated fees — all in one printable PDF for Gresham, Oregon.
Download the Complete Gresham ADU Cheat Sheet — $12Frequently Asked Questions About ADUs in Gresham
Can I build an ADU in Gresham?
Gresham permits ADUs under Oregon law. The city offers SDC reductions for ADUs to encourage construction.
How big can my ADU be in Gresham?
What is the maximum ADU size allowed in Gresham? ADUs in Gresham can be up to 1,200 square feet, subject to the property's zoning and lot coverage limits. Always confirm the exact allowed size with the Gresham planning department before designing your project.
What about setbacks and other requirements in Gresham?
What are the setback requirements for an ADU in Gresham? ADUs in Gresham generally require setbacks of 5 ft rear, 5 ft side. California state law (AB 68) limits local setback requirements to 4 feet for existing structures, but always verify with local zoning.
Looking for other Oregon cities?